The older SPARCs (and perhaps some of the Ultras?) use a Zilog chip for


all the sbus-based ultrasparcs have zilog serial chips.  i, fwiw, i've had
success with sparc serial ports at 38400 for most of the past 4 or 5 years
(i've been using them pretty much ever since netbsd/sparc first appeared,
but the driver was more lame back then).